Environmental Science: Nano最新文献

In order to reduce phosphorus (P) losses due to P leaching, enhance the adsorption capacity of soil for P, and ensure environmental safety and optimal crop growth, a multitude of calcium-containing natural minerals and industrial-synthesized materials have been employed in a vast array of applications. However, the potential of nano calcium carbonate (NCC) with high surface electronic activity and a large specific surface area to serve as ideal slow-release P fertilizers has rarely been explored in academic research. In this study, the optimum application rate of NCC and its effect on soil P processes were determined by setting up five different treatments, namely, 0 NCC, 0.15% NCC, 0.30% NCC, 0.45% NCC, and 0.60% NCC, through a soil column leaching experiment as well as a two-year field experiment (2020–2022). The results showed that all treatments of NCC reduced leaching losses of soluble P. Compared with 0 NCC, 0.30% NCC and 0.45% NCC increased soil available P (AP) content and alkaline phosphatase (ALP) activity. In comparison to the 0 NCC, the 0.30% NCC treatment resulted in a notable increase in the relative abundance of several bacterial groups, including Actinobacteria, Acidobacteria, Haliangium, Solirubrobacter, Actinoplane, Nocardioides, Dongia, and Gemmatimonas. Additionally, the relative abundance of ppx, ppa, and phoD was elevated, while the relative abundance of Firmicutes, Bacillus, phnE, and phnC was reduced. The 15% NCC treatment resulted in a notable increase in the abundance of gcd. NCC treatments increased P concentrations in wheat stems, leaves, and spikes. NCC promoted wheat P uptake by regulating the rate of P release, and by activating ALP activity and increasing soil AP content by promoting soil bacterial-mediated mineralization of organic P and solubilization of inorganic P.

Proteins like albumin are found in various environmental and living systems, and they have wide applications in various fields. It is known that the functional, conformational and sorption properties of proteins are significantly affected by various surrounding conditions and chemicals. Micro-/nano-plastics are an emerging issue for the environment, living systems and industrial applications, and they can easily leach, sorb and/or desorb chemicals. These processes can change medium characteristics. However, studies on the impact of micro-/nano-plastics on the chemical and biological behaviors of proteins are lacking. Herein, we investigated the interactions between bovine serum albumin and polyethylene terephthalate micro-/nano-plastics by assessing the binding, structural and oxidative characteristics of proteins using UV-VIS, fluorescence and Raman spectroscopies and molecular docking studies. Additionally, the biological impact of non-treated and micro-/nano-plastic-treated proteins was examined by assessing cytotoxicity (mitochondrial activities and membrane integrity) and oxidative stress (antioxidants, reactive oxygen species, catalase, glutathione reductase, and superoxide dismutase) of a human lung epithelial cell (A549) in vitro model. Binding results showed that micro-/nano-plastics had an affinity for proteins and varied according to the exposure concentration and duration. Molecular simulations revealed that micro-/nano-plastics were bound to the active sites of proteins, which caused structural and functional changes. Raman spectral results further confirmed the structural changes in the proteins after the treatments. Moreover, it was observed that the chemical (e.g., zeta potentials, aromatic side chains and folding) and oxidative indicators of proteins were significantly affected. The exposure of lung cells to non-treated and micro-/nano-plastic-treated proteins resulted in different mitochondrial and membrane activities. The oxidative stress indicators revealed that antioxidants, reactive oxygen species and their balance were significantly affected, and the cell viabilities of superoxide dismutase and glutathione reductase were more influenced than those of catalase. The correlation results also indicated that folding, aromatic chain, quenching constant and oxidative potentials of proteins were more effective indicators of the cellular responses of micro-/nano-plastics-treated proteins than zeta potentials. Thus, all the results indicated the side effects of micro-/nano-plastics on proteins owing to their leaching and sorption.

Muskmelon Fusarium wilt (MFW) disease caused by Fusarium oxysporum f. sp. melonis (FOM) is one of the major challenges faced in muskmelon production worldwide. Trichoderma sp., as a well-known biocontrol fungus, and AgNPs have been widely used to control plant diseases. However, few literature studies have been reported on the combined application of AgNPs and Trichoderma sp. against soil-borne diseases. This study was aimed at investigating the inhibitory effect of AgNPs and Trichoderma sp. to FOM and the control effect of the combined application of AgNPs and Trichoderma koningiopsis (TK) against MFW. The characteristics of different AgNPs were also analyzed using various techniques, such as XRD, TEM-EDS, FTIR and TEM. Results showed that TK had the highest inhibition rate (63.77%) against FOM among the four Trichoderma strains and had the best resistance to AgNPs, with an average inhibition rate of 5.76% on mycelium growth. Different AgNPs and their combinations had different inhibitory effects on the growth and sporulation of FOM. The inhibition rate of the AgNPs-TH (T. hamatum) and AgNPs-TK (T. koningiopsis) combination (AgNPs-C) was the highest, reaching up to 50.83%. The specific absorption peaks of AgNPs-TH, AgNPs-TK and AgNPs-C occurred at 420 nm, 323 nm and 320 nm, respectively. XRD and TEM-EDS showed that the crystalline structured nanoparticles were spherical with a diameter ranging from 16.5 nm to 23.4 nm. FTIR results showed that there were more functional group moieties (–OH, –CH₃, –C–O, etc.) on AgNPs-C, which were involved as a capping and reducing agent in the biosynthesis of AgNPs. The combined application of AgNPs-C and TK decreased the incidence (11.11%) and disease index (2.78) compared with CK-F (77.78% and 48.61, respectively) and improved the growth and plant fresh weight. Thus, the combined application of AgNPs and biocontrol agent (TK) could be used to improve the growth and development of muskmelon and suppress the MFW disease, providing an alternative approach to realize an eco-friendly control of the soil-borne disease.

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants that pose significant risks to the environment and human health. Phenanthrene (PHE), a model PAH, has been shown to cause toxic effects on plants, particularly on their photosynthetic performance. This study investigated the potential of nano-biochar (nBC) derived from rice straw to alleviate the phytotoxicity of PHE in wheat seedlings. We hypothesized that the high adsorption capacity and unique properties of nBC, such as its high surface area, porous structure, and abundant functional groups, could reduce the bioavailability and toxicity of PHE, thereby mitigating its adverse effects on wheat growth and photosynthesis. Wheat seedlings were exposed to different treatments, control, 1.0 mg L⁻¹ nBC, 1.0 mg L⁻¹ PHE, 1.0 mg L⁻¹ PHE + 0.5 mg L⁻¹ nBC, and 1.0 mg L⁻¹ PHE + 1.0 mg L⁻¹ nBC. The results showed that nBC alleviated PHE-induced chlorosis and improved plant growth. Compared to the PHE-single treatment, the application of 1.0 mg L⁻¹ nBC increased chlorophyll content by 14.54% and enhanced photosynthetic efficiency, as evidenced by increases in Fv/Fm (2.48%), q_P (9.06%), and Φ_PSII (3.81%). Furthermore, nBC reduced the accumulation of PHE in wheat tissues, with the PHE concentration in the PHE-single treatment being 1.77 and 1.61 times higher than that in the 1.0 mg L⁻¹ nBC treatment for shoots and roots, respectively. The non-photochemical quenching (NPQ) values decreased by 13.64% in the presence of 1.0 mg L⁻¹ nBC, indicating reduced heat dissipation and improved photosynthetic performance. The alleviation of PHE toxicity by nBC can be attributed to its high adsorption capacity, which limits the uptake of PHE by plants. Additionally, the photoelectric effect of nBC may directly promote photosynthesis by enhancing electron transport and providing reducing power for ATP and NADPH synthesis. The use of nBC for the remediation of PAH-contaminated soils offers several advantages, including sustainability, eco-friendliness, and additional benefits such as carbon sequestration and soil quality improvement. These findings highlight the potential of nBC as an effective amendment for the remediation of PAH-contaminated soils and the protection of crops under PAH stress.

Carbon black (CB) is a man-made, pure carbon particle with numerous applications in a variety of commercial and consumer products. Upon inhalation, it may bioaccumulate in various organs, raising serious health concerns. However, biotransformation processes that CB undergoes can alter its chemical and physical properties, thereby affecting its toxicities. When airborne CB is exposed to UV radiation, it undergoes an aging process. Upon entering physiological environments, biomacromolecules, such as proteins, rapidly adsorb onto CB's surface, forming a protein corona that mediates cellular interactions. Our study reveals that ozone aging influences the adsorption of CB in mouse plasma. Exposure to pristine CB and ozone-aged carbon black (CB-O₃) triggers inflammatory responses in J774A. 1 macrophage cell lines and activates the NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome. Notably, ozone aging and plasma protein corona adsorption enhance CB uptake by J774A. 1 cells, thereby increasing its cytotoxicity. Mechanistically, CB and CB-O₃ exposure induce lysosomal damage and dysfunction, leading to cathepsin B release and activating the NLRP3 inflammasome. Importantly, this activation correlates with a reduction in blood–testis barrier-associated protein expression. In vivo experiments confirm that prolonged exposure to CB and CB-O₃ activates the NLRP3 inflammasome within the testes, leading to a significant compromise of the blood–testis barrier integrity in mice. These findings highlight the importance of considering environmental aging processes and protein corona formation in toxicological evaluations, offering a more comprehensive framework for regulatory policies and protective measures aimed at mitigating the adverse health impacts of CB exposure. Additionally, this study underscores the potential for targeting the NLRP3 inflammasome pathway in therapeutic strategies to alleviate CB-induced inflammatory and reproductive toxicity.

Humans are constantly exposed to microplastics and nanoplastics (MNPs). Although significant gaps remain in our understanding of their adverse effects on human health, it is increasingly evident that MNPs can penetrate physiological barriers and accumulate in various locations within the human body. Analytical limitations in tracking and measuring nanoplastics in physiological media may persist for several years before we can accurately detect these particles in the human body and establish a clear link between exposure to them and associated hazards. In addition to the few studies that have emerged recently, our knowledge of chemicals with properties similar to those of MNPs, as well as other types of nanomaterials, suggests that MNPs may cross the blood–brain barrier (BBB) and potentially induce damage to the human central nervous system. Here, we provide an overview of the limited number of studies available on this topic and present a perspective on the potential pathways through which MNPs may penetrate the BBB. We also discuss the main mechanisms by which MNPs could potentially impact the central nervous system (CNS), with a focus on neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), and amyotrophic lateral sclerosis (ALS). This information could contribute to the development of tailored studies exploring the negative effects of MNPs on the CNS.

The term advanced materials (AM) is used widely to cover a large number of diverse new innovative materials, including nanomaterials, advanced composites, innovative surface coatings, (bio)polymers, porous and particle systems, ceramics, smart and metamaterials and advanced fibres and textiles. With any new materials, there are commercial and performance advantages that need to be balanced with any potential environmental, health and safety issues, for example, around exposure, toxicity, sustainability and waste. Key players in the UK from government bodies, research, measurement and standardisation organisations, academia and industry came together to consider these issues via two online workshops in April 2021 and February 2023. At each event, scene-setting presentations by key experts were followed by discussions addressing salient issues, including, benefits and barriers to AM commercialisation, potential environmental, health and safety issues, and safe(r) by design approaches. The first workshop served as a starting point to share views on the potential societal benefits of AM and perceived obstacles to their wider adoption. The second workshop focused on safety by design, life cycle analysis and challenges faced at different points in the supply chain. In addition to confirming findings from previous studies, these workshops also highlighted specific challenges that are faced by small to medium sized enterprises (SME). These workshops provided a unique opportunity for policy makers, regulators, standardisation bodies, funding bodies and academia to understand the concerns of industry and researchers, who develop and work with AM. This included what they felt would help support them in their aims of developing innovative, commercially successful, safe and sustainable AM.

Transparent non-wetting surfaces with mechanical robustness are critical for applications such as contamination prevention, (anti-)condensation, anti-icing, anti-biofouling, etc. The surface treatments in these applications often use hazardous per- and polyfluoroalkyl substances (PFAS), which are bio-persistent or have compromised durability due to weak polymer/particle interfacial interactions. Hence, developing new approaches to synthesise non-fluorinated liquid-repellent coatings with attributes such as scalable fabrication, transparency, and mechanical durability is important. Here, we present a water-based spray formulation to fabricate non-fluorinated amphiphobic (repellent to both water and low surface tension liquids) coatings by combining polyurethane and porous metal–organic frameworks (MOFs) followed by post-functionalisation with flexible alkyl silanes. Owing to intercalation of polyurethane chains into MOF pores, akin to robust bicontinuous structures in nature, these coatings show excellent impact robustness, resisting high-speed water jets (∼35 m s⁻¹), and a very low ice adhesion strength of ≤30 kPa across multiple icing/de-icing cycles. These surfaces are also smooth and highly transparent, and exhibit excellent amphiphobicity towards a range of low surface tension liquids from water to alcohols and ketones. The multi-functionality, robustness and potential scalability of our approach make this formulation a good alternative to hazardous PFAS-based coatings or solid particle/polymer nanocomposites.

The development and application of engineered nanomaterials has required pushing the boundaries of analytical instrumentation in order to detect, quantify and characterize the properties and behaviors of materials at the nanoscale. One technique, single particle ICP-MS, has stood apart for its ability to characterize and quantify inorganic nanomaterials at low concentrations and in complex environmental and biological media. For the past 20 years, this technique has matured significantly, with an ever-expanding scope of application. Where initially it was capable of analyzing precious metal nanoparticles in relatively pristine solutions, now it can be used to characterize multiple different NP populations of varying elemental and isotopic compositions. The types of materials analyzed now extend beyond traditional metallic NPs, with varied materials such as nanominerals, carbon nanotubes, biological cells, and microplastics. In this perspective, we examine the key developments in the past decade of spICP-MS and aim to provide a vision for what this field may look like 10 years from now. The study of nanoparticles, both natural and engineered, will continue to play a vital role in our understanding of climate change, anthropogenic impact, and biogeochemical cycling of nutrients and contaminants in a rapidly changing environment.

Developing efficient, non-toxic (or low toxicity), low-cost, and long-lasting antibacterial and algae-inhibiting materials is an important issue closely related to human health. Coral sand, due to its porous and biologically residual nature, is an environmentally friendly pure natural material, and its application in the field of environment has attracted attention. This study used coral sand as a carrier to immobilize nano silver and obtained the composite material coral sand-Ag (CS-Ag), which could release nano silver in a slow-release manner to achieve the purpose of continuous sterilization and algae inhibition. The research results showed that 44.2% of silver ions could be sustained within one week, demonstrating a silver sustained release effect. There were obvious antibacterial circles around the CS-Ag composite material, with a diameter of 22.5 ± 0.1 mm for Staphylococcus aureus and 24.1 ± 0.1 mm for Escherichia coli. The bactericidal activity of silver-loaded coral sand was affected by environmental temperature and pH value. SEM observations showed that silver-loaded coral sand caused scars or holes on the surface of bacterial cells, which also confirmed its ability to damage bacterial cells. This material also had an inhibitory effect on single-cell algae. In the treatment group with a concentration of 1.0 g L⁻¹, the inhibition efficiency of CS-Ag on the growth of microalgae for 96 h can reach 89.7%. The addition of silver-loaded coral sand also affected the structural morphology of algal cells and the synthesis of chlorophyll a, thereby inhibiting photosynthesis and respiration, respectively. The high concentration of silver-loaded coral sand almost completely inhibited the photosynthesis and respiration of algal cells. Therefore, CS-Ag is expected to achieve the removal of bacteria and algae in intensive aquaculture water and achieve harmless disease control.